Equipment Maintenance & Operations Flashcards

What is the function of an expansion loop or expansion joint in a petroleum pipeline system?

Answer: To absorb thermal expansion and contraction of the pipe

Expansion loops and joints accommodate dimensional changes in piping caused by temperature variations, preventing stress and potential pipe failure.

A positive displacement pump differs from a centrifugal pump primarily because it:

Answer: Delivers a fixed volume of fluid per revolution regardless of pressure

Positive displacement pumps move a fixed volume per stroke or revolution, making their output relatively independent of discharge pressure.

During a compressor oil analysis, a high silicon content reading typically indicates:

Answer: Air filter failure or bypassing

Silicon is a major component of airborne dirt; elevated silicon in compressor oil indicates that the air filter has failed or air is bypassing the filter.

What is the purpose of a 'bump test' when starting a motor-driven pump for the first time after maintenance?

Answer: To verify correct rotation direction before full operation

A bump test briefly energizes the motor to confirm it rotates in the correct direction, preventing damage from reverse rotation.

Which instrument is used to measure the thickness of a pipe wall to detect corrosion without cutting into the pipe?

Answer: Ultrasonic thickness gauge

An ultrasonic thickness gauge sends sound waves through the pipe wall and measures the return signal to determine wall thickness non-destructively.

A storage tank is equipped with a floating roof. What is the PRIMARY advantage of this design?

Answer: It minimizes vapor space to reduce evaporative losses and fire risk

A floating roof rises and falls with the liquid level, virtually eliminating the vapor space above the product to reduce evaporation and explosion risk.

When replacing a control valve actuator, what is the correct procedure for setting the valve positioner?

Answer: Calibrate using the full input signal range (e.g., 4–20 mA) to match 0–100% valve travel

Proper positioner calibration requires applying the full input signal range to verify the valve travel matches the signal from fully closed to fully open.